摘要:

Li foils for transmission electron microscopy were prepared by shaving a Li bar in a dry box under an Ar atmosphere. The specimen was transferred to the microscope using a modified Hitachi specimen exchange device. Li single‐crystal diffraction patterns were observed. The microstructure consisted of small grains containing rapidly moving dislocations.

ISSN:0003-6951    

DOI:10.1063/1.1652688

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Li thin foils of 1‐&mgr; thickness or more were observed by conventional electron microscopy with 100‐keV electrons. The dislocation structure has been analyzed at 300°K and around 100°K in the bcc phase of Li. Dislocation slip planes are of the {112} types and most dislocations are parallel to ⟨110⟩ directions.

ISSN:0003-6951    

DOI:10.1063/1.1652689

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

In this paper, a video display system for direct imaging of transmission and reflection x‐ray topographs of Si and GaAs wafers is described. This system allows instantaneous viewing of x‐ray topographs with fields of view on the order of 2 cm by 1 cm. The resolution of the system is now limited by the sensitivity of the x‐ray phosphor to about 30 &mgr;. Slip bands and diffused devices have been directly observed in both Si and GaAs, as have been accidentally induced damage such as scratches and wafer warpage. Also, Laue patterns for orientation of wafers and ingots can be directly viewed, eliminating the time consuming method of film techniques.

ISSN:0003-6951    

DOI:10.1063/1.1652690

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Efficient doping of GaAs by ion implantation has been obtained using Se+ions. For a Se+dose of 3 × 1012/cm2implanted at 400 keV, a peak carrier concentration of 2 × 1017/cm3occurred at a depth of 750 Å, with a standard deviation of 500 Å. Integration of the excess carrier concentration caused by the implantation indicates that for this ion dose at least 50% of the implanted ions are electrically active. For larger doses the doping efficiency decreases, and the carrier concentration approaches a limiting value of approximately 1019/cm3. The lowest observed sheet resistance for the implanted layer, about 250 &OHgr;/square, occurred for a Se+dose of 2 × 1014/cm2.

ISSN:0003-6951    

DOI:10.1063/1.1652691

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Trapping‐detrapping pulse shapes have been observed in two Si(Li) detectors in the temperature range 8.5–70°K. A semiquantitative treatment leads to the conclusion that shallow trapping levels are responsible for the observed phenomena. It appears likely that these levels correspond to the donor (Li) and acceptor (B) dopants; if this hypothesis is confirmed by further experimental work it establishes a low‐temperature limit on the use of semiconductor detectors for &ggr;‐ray and high‐energy particle spectroscopy.

ISSN:0003-6951    

DOI:10.1063/1.1652693

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Line centers of a number of previously unresolved SF6transitions of the fundamental &ngr;3band have been observed and their frequencies have been determined relative to theP‐branch transitions of the CO210.6‐&mgr; laser. Measurements of dip widths at small saturation levels yielded a determination of the SF6&sngbnd;SF6cross section for phase interruption. Observation of a multiplicity of absorption line centers over the tuning range of theP(20) laser transition, several well within one SF6Doppler width of 29 MHz, verifies the complex nature of theP(20) line absorption found by other workers.

ISSN:0003-6951    

DOI:10.1063/1.1652694

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Absorption of CO2laser lines by SF6was studied by several methods for variousPlaser lines of the 00°1–10°0 band. It is concluded that the absorption of theP20 line is mainly due to the several SF6lines withJvalues between 50 and 80.

ISSN:0003-6951    

DOI:10.1063/1.1652695

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

The well‐known convolution technique was used to measure subnanosecond pulses generated from ``filaments'' in a self‐focused beam. The results showed that in toluene, the pulse width varied from 200 to 100 psec or less, and the peak power was about 30 kW.

ISSN:0003-6951    

DOI:10.1063/1.1652696

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Spectrographic techniques have been used to determine electron temperatures and densities in the interelectrode plasma of a close‐spaced high‐current cesium plasma diode. These results were obtained from the relative intensity of the radiative recombination continuum and measured line‐widths, respectively, of cesium. The diode was operated at two short‐circuit current conditions (∼15 and 18 A/cm2) with an interelectrode spacing of 0.25 mm. Contrary to some theories, these results indicate that steep temperature gradients do exist in the plasma and that maximum electron temperatures are 2800°K.

ISSN:0003-6951    

DOI:10.1063/1.1652697

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

The pulsed water‐vapor laser has been operated at peak output power levels of 5 kW (all lines) and an average power of ¼ W. The frequency of the most energetic component of the emission has been measured to be &ngr;¯ = 357.506 ± 0.003 cm−1.

ISSN:0003-6951    

DOI:10.1063/1.1652698

出版商:AIP    

年代:1969

数据来源: AIP